<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <!--JavaScript-->
    <script>
        // 1.定义变量
        var num = 1;
		// 2.条件控制
		if (2 > 1) {
            alert("true");
        }
    </script>
</head>
<body>

</body>
</html>